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Pibs
30-07-2004, 09:43 AM
Question, if adding memory of different speeds, what would be the result?
I have DDR400 512mb. If I install another stick DDR330 512mb would the PC read it all at DDR330, and would there be any disadvantage? I have both," to install or not to install" that is the question. As somebody once wrote.
Pibs ?:1

CYaBro
30-07-2004, 09:50 AM
The result would be that all RAM would run at the slower speed, but then you have to way up the advantage of having 1GB instead of just 512MB.
What are the rest of the specs of the PC? as that might sway the decision.

godfather
30-07-2004, 09:52 AM
If your motherboard/CPU requires the higher speed, then you will be "crippling" the system, as you will have to underclock the RAM speed.

If it only needs and uses 333 memory, then it will all run as 333 as it must be now.

Its a lottery as to the mix being stable. Some are, some are not. I have a speed mix here, all running at the lower speed and its stable.

Your mileage may vary however.

tweak\'e
30-07-2004, 09:53 AM
depends on what speed the system runs at. if its using the DDR400 at 400 then adding a DDR333 is going to slow the pc down or cause it to be crash happy. if the DDR400 is running at 333 then its OK to add a DDR333. personally i wouldn't. keep all the stick the same speed if possible.

Pibs
30-07-2004, 10:07 AM
Thanks for the replies, the specs are:-
AMD 2800 and I am thinking of putting in the radeon 9600 pro from DSI. I ran Everest Home Edition on the PC and it tells me to add more memory and that the graphics are slow, the PC is about 3 months old.
G F are you saying try it? That I don't mind as long as I do no harm, thanks
Pibs

Pibs
30-07-2004, 10:08 AM
Thank you tweake I will err on the side of caution
Pibs

metla
30-07-2004, 10:22 AM
The 2800 only runs a fsb of 333,ignore everything said so far and stick your ram in.

You will end up with a boatload of ram running at optimal speed for your rig.This is GOOD.

Do it.

CYaBro
30-07-2004, 10:34 AM
> The 2800 only runs a fsb of 333

That's what I was waiting for. The DDR400 RAM you have will only be running as DDR333 so I'm with metla on this one.

tweak\'e
30-07-2004, 11:30 AM
>You will end up with a boatload of ram running at optimal speed for your rig

not quite that easy. general rule of thumb is the DDR400 running at 333 will run at a faster cas setting than a DDR333. so for optoimal speed make sure to get a good DDR333 not just a generic. you may find a generic DDR400 cheaper than a good brand DDR333 and both will run the same.

Pibs
30-07-2004, 11:30 AM
Caution to the wind then, oh the trust we put in fellow F1 ers.
thanks everyone for the help

Pibs

tweak\'e
30-07-2004, 11:33 AM
DOH ! silly me i forgot :(

>The 2800 only runs a fsb of 333

dosn't always make any differnce as some motherboards run the ram speed seperatly from the fsb eg you can have DDR400 running at 400 on a 333 fsb motherboard.

check what the motherboard can use/run

Pete O\'Neil
30-07-2004, 11:42 AM
> I ran Everest Home Edition on the
> PC and it tells me to add more memory and that the
> graphics are slow, the PC is about 3 months old.

You rush out and buy new hardware because a peice of software told you too?

metla
30-07-2004, 11:47 AM
> dosn't always make any differnce as some motherboards
> run the ram speed seperatly from the fsb eg you can
> have DDR400 running at 400 on a 333 fsb motherboard.

That is true,however running 400ddr ain't gonna do anything when the cpu is running at 333,Putting both sticks in at 333 will however get the thing smokin along.

The only benifit for 400 in a system running a 333 fsb is that you can run the 400 at 333 and then fiddle with the ram timings,if my terminology is correct you can lower the cas by .5

tweak\'e
30-07-2004, 12:21 PM
>however running 400ddr ain't gonna do anything when the cpu is running at 333

the cpu isn't the only thing to use the ram ;-)

>Putting both sticks in at 333 will however get the thing smokin along.

i doubt it. except for certain programs you will only get a minor increase in speed. proberly not worth the $$$ for the average user. you can gain more speed by tweaking windows :)

>he only benifit for 400 in a system running a 333 fsb is that you can run the 400 at 333 and then fiddle with the ram timings

no need to fiddle in most cases as it auto selects the timings (tho you can tweak it to go a bit faster ;-) )

after all the difference between DDR333 and DDR400 is proberly only $10-$20 anyway.

Pibs
30-07-2004, 12:25 PM
No Pete, it's just that I have the 330 spare

metla
30-07-2004, 12:37 PM
> >however running 400ddr ain't gonna do anything when
> the cpu is running at 333
>
> the cpu isn't the only thing to use the ram ;-)

Run a benchmark or 3,the system will be able to perform better with 1gb at 333 then 512mb stick running at 400 on a system that only makes use of 333fsb

Perhaps i should run a benchmark with the ram at 400mhz,then change it to 333 to sync with the cpu then run it again?


>
> >Putting both sticks in at 333 will however get the
> thing smokin along.
>
> i doubt it. except for certain programs you will only
> get a minor increase in speed. proberly not worth the
> $$$ for the average user. you can gain more speed by
> tweaking windows :)

Limited agreement with you,but its a moot point,of course only apps that make use of the extra ram will benifit from it,And that sort of advantage is in no way available from tweaking windows.
>
> >he only benifit for 400 in a system running a 333
> fsb is that you can run the 400 at 333 and then
> fiddle with the ram timings
>
> no need to fiddle in most cases as it auto selects
> the timings (tho you can tweak it to go a bit faster
> ;-) )

aye?...the point was that if you run ddr400 at 333mhz you can then lower the cas(from 2.5 to 2.0),the autoselect will only select default,giving no advatage,User input is needed.


>
> after all the difference between DDR333 and DDR400 is
> proberly only $10-$20 anyway.

I believe he already has a stick of ram

kiki
30-07-2004, 12:38 PM
I would buy another DDR400 stick of the same type, see if you can get it to run it in dual channel if the motherboard supports this, then overclock the FSB a bit to make use of the RAM, and then lower the RAM timings.

tweak\'e
30-07-2004, 12:50 PM
>Run a benchmark or 3.......

every benchmark tests it differently. what really matters is the speed of the programs they are useing.

>the autoselect will only select default,giving no advatage,User input is needed.

i've never needed to manually adjust it as the bios auto sets it to the best. eg my own runs ddr333 @ 266 cas2 but if you use it in a 333 system it runs at cas3. the settings are determined by the ram, provided the bios knows how to use them which unfortunatly dosn't always happen and user intervention is required.

seeing he already has the ram then he can simply stick it in and see what it runs like. if any improvement then sweet, otherwise keep it out. if he said that in the first post it would have saved a lot of typing ! ! ! ;-)

Pibs
30-07-2004, 06:36 PM
Thanks to all the replies, I had the spare RAM but didn't want to do any thing nasty to the PC. Thought if I have it try to use it or give it to anyone in the family if it's no good to me. I have put it in and tried Flight Sim, (the only game I have) and as a point of interest I can't see any difference in ANY application, there are no crashes or error signs and seems to be running just fine, so as there is no improvement I will take it out and not tempt fate. Thanks again for your imput and patients.

Pibs